A-size underwater vehicles (i.e., those having a size of about 4⅞″ diameter×36″ long) are often used as simulators for testing a variety of Navy shipboard systems. For example, such vehicles can be outfitted with systems that simulate the noise of a submarine or other water-borne vehicle or device, and are used to teach other systems to detect and recognize such noises as being associated with that specific device.
Currently there are no A-size underwater vehicles that employ stable, energy efficient, linear controls. At present, these small underwater vehicles have directional controls that are either binary (i.e., on-off) controls or which use linear motors that must be constantly electronically actuated to hold the vehicle on a desired position or course. Binary controls, which apply either full left rudder or full right rudder, cause the vehicle to swim erratically, while linear motors use too much power, since they employ a solenoid that must be constantly “on” in order to hold the rudder/elevator at a particular position. Thus, there is a need for an improved control system for an underwater vehicle that is stable, and that requires less power than existing systems.
Furthermore, current A-size underwater vehicles employ fixed payload sections which, as previously noted, may contain devices such as noisemakers for simulating the noise signature of a particular water-borne vehicle or device. Having a fixed payload section, however, limits use of the vehicle to specific applications and thus a larger number of such vehicles must be kept on hand to address a typical array of testing requirements. Thus, there is a need for an improved underwater vehicle having a simple modular payload arrangement that allows a variety of payloads to be simply and efficiently interchangeable with a single vehicle body.